德·瓦莱拉后来被任命为国民议会的主席,并在1919年5月,他以这个身份访问了美国。这次出访有三个目标:要求美国正式承认爱尔兰共和国,提供一笔贷款资助爱尔兰共和军的工作,并确保美国人民对爱尔兰共和国的支持。他的访问从1919年6月持续到1920年12月,成败参半。一个消极的结果是,爱尔兰裔美国人组织分裂成亲德·瓦莱拉和反德·瓦莱拉两派。[12]德·瓦莱拉设法从美国支持者那里筹集了550万美元,这个数字远远超出了国民议会的预期。.[13]其中50万美元用于1920年的美国总统竞选,以帮助他在那里获得了更广泛的公众支持。[14]在1921年,据说已经花费了$1,466,000,不清楚什么时候剩下的钱能够到达爱尔兰。[15]但是爱尔兰在国际领域还没有得到承认。他还与多位爱尔兰裔美国人领袖发生过争执,比如约翰·德沃伊(英语:John Devoy)和丹尼尔·F·科哈伦(英语:Daniel F. Cohalan)法官。科哈伦对他确立的主导地位感到不满,他宁愿保留他们对爱尔兰裔美国人事务的控制权,也不愿意在瓦莱拉的主导下独立。
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